Madeleine McCann's parents have hit out at the coverage of the latest developments in the investigation into the disappearance of their missing daughter, as Scotland Yard detectives arrived in Portugal to meet with their counterparts.
Search teams are expected to start excavating a number of sites in Praia da Luz, where Madeleine - then aged three - went missing on May 3 2007 , after they were given permission by Portuguese authorities.
But it is believed that a request to search the homes of three men suspected of a number of break-ins before the youngster's disappearance has been turned down.
It is also thought that friction has developed between police teams over the media coverage of the latest developments.
Scotland Yard commissioner Sir Bernard Hogan-Howe today told Sky News: "There are always going to be complications when you have got one police force in one country working with the police force of another.
"We have both got to be sensitive to these things.
"The critical thing is, as Madeleine's parents have said and we all support, is that they need to have some closure on this, they need to know what happened to their daughter."
In a statement on their Find Madeleine website, Kate and Gerry McCann criticised the media saying: " There is an on-going, already challenging, police investigation taking place and media interference in this way not only makes the work of the police more difficult, it can potentially damage and destroy the investigation altogether - and hence the chances of us finding Madeleine and discovering what has happened to her.
"As Madeleine's parents, this just compounds our distress."
The request to excavate several sites in the area is not thought to necessarily be in connection with a search for Madeleine's body or remains and is thought to be among a series of requests made by British detectives in connection with the investigation.
The McCanns' spokesman Clarence Mitchell has previously said: ''As always, we simply will not comment on operational details of Operation Grange, that is a matter for the Met Police.
''Kate and Gerry are being kept fully informed throughout.''
As they marked the seventh anniversary of Madeleine's disappearance last weekend, Mr and Mrs McCann thanked the public for their unstinting support and Mr McCann expressed his family's gratitude that the police investigating Madeleine's disappearance were moving on to a ''very active'' phase in their investigation, saying: ''They are chipping away and obviously there is new evidence so we are going to continue to hope that we will get a happy outcome.''
Earlier, Mrs McCann disclosed that she privately returns to the Portuguese resort where her daughter disappeared to ''walk those streets'' and ''look for answers'', as she backed a revamped alert system triggered when missing children are kidnapped or their lives are at risk - known as Child Rescue Alerts.